Quantifying Slowness in Parkinson Disease Using a Serious Game: Cross-Sectional Study

Area of Science:

• Biomedical Engineering
• Neuroscience
• Digital Health

Background:

• Slowness of voluntary movement is a key Parkinson disease (PD) symptom.
• Objective motor assessment for PD outside clinical settings is challenging.
• Serious games offer potential for extracting motor performance metrics.

Purpose of the Study:

• To objectively assess motor slowness in Parkinson disease (PD) using the RehaBEElitation serious game.
• To evaluate the effectiveness of in-game measurements for discriminating PD motor performance.
• To explore the utility of serious games as digital biomarkers for PD.

Main Methods:

• 15 individuals with PD (ON/OFF medication) and 15 healthy controls played the RehaBEElitation game.
• Singular spectrum analysis of gyroscope signals evaluated voluntary movement slowness.
• Response time (RT) and angular velocity (AV) were extracted from gameplay.
• Kruskal-Wallis and Wilcoxon signed rank tests compared groups; eta square (η2) estimated effect size.
• Spearman correlations examined associations between RT/AV and MDS-UPDRS motor scores.

Main Results:

• Healthy controls exhibited shorter RT and higher AV than individuals with PD.
• In PD patients, medication improved motor performance (decreased RT, increased AV).
• Significant group differences in RT were found across all game phases (small to moderate effect sizes).
• Angular velocity (AV) showed a large effect size difference between groups in phase 4 (η2=0.404).
• AV strongly correlated negatively with bradykinesia scores (MDS-UPDRS).

Conclusions:

• The RehaBEElitation serious game, using inertial sensor data, provides objective motor measures (RT, AV) for PD slowness assessment.
• Gameplay metrics can detect motor differences related to slowness, supporting serious games as digital biomarkers.
• This approach enables continuous, quantitative evaluation beyond traditional clinical methods, with potential for remote monitoring.